In the second quarter of Game 2, the All-Star center was called for a flagrant foul 1 after swinging his arm so that his elbow swept through the head of the Celtics' Paul Pierce, who tumbled to the floor clutching his head in pain. Both players remained in the game.
The NBA reviews all flagrant foul calls, and officials spent part of Wednesday deciding whether to upgrade Howard's foul to a more serious flagrant 2 or suspend him for Game 3. A league spokesperson said the play will "stand as called."
The NBA has a track record of punishing blows to the head severely. Howard himself was suspended for a first-round playoff game last season against the Philadelphia 76ers after swinging an elbow at the head of Samuel Dalembert.
Henry Abbott writes for ESPN.com's TrueHoop blog.